Automatic grinder-stone dresser



F. E. RILEY.

AUTOMATIC GRINDER STONEJDRESSER.

APPLICATION FILED JULY 25,1919.

Patented Mar. 9, 1920.

3 SHEETS-SHEET I- I .2 an

III/VENTOR ATTORNEYS I I I WITNESSES F. E. RILEY.

AUTOMATIC GRINDER STONE DRESSER.

APPUCATlON FILED JULY 25.1919. 1,333,445. Patented Mar. 9, 1920.

3 $HEETS-SHEET 2- WITNESSES g INVENTOR W ATTORNEYS F. E. RILEY.

AUTOMATIC GRINDER STONE DRESSER.

I APPLiCAT DN FILED JULY 25| I919. 1,333,445. Patented Mar. 9, 1920.

3 $HEETS-SHEET'3.

JEWLZZ WITNESSES 4 TTORNEYS FRED E. RILEY, OF LIVERMORE FALLS, MAINE.

AUTOMATIC GRINDER-STONE DRESSER.

Specification of Letters Patent.

Patented. Mar. 9, 1920.

. Application filed July 25, 1919. Serial No. 313,284.

To all whom it may concern.-

Be it known that I, FRED E. RILEY, a citizen of the United States, and aresident of Livermore Falls, in the county of Androscoggin and State ofMaine, have invented a new and Improved Automatic Grinder- StoneDresser, of which the following is a full, clear, and exact description.

This invention relates to a number of important specific improvementsover the subject matter of Letters Patent of the United States No.1,268,624, issued to me on the 4th day of June, 1918.

Among the objects of the invention is to so improve the construction asto make it more practical and reliable in use and accurate in operation.

More specifically stated among the objects of the present improvement isto provide a main carriage having inlet and eX- haust ports for thepower fluid formed directly therein.

Another object of the invention is to provide improved speciallyconstructed valves and operating means therefor of an automatic naturewhereby the continual to and fro reciprocation of the main carriage anda similar forward and rearward movement of the cross feed motor may beacand the main carriage through which I am able to secure any desiredextent of reciprocation of the cross feed motor with a rela tivelyslight reciprocation of the valve shifting member actuated by or fromsaid cross feed motor.

With the foregoing and other objects in view the invention consists inthe arrangement and combination of parts hereinafter described andclaimed, and while the invention is not restricted to the exact detailsof construction disclosed or suggested herein, still for the purpose ofillustrating a practical embodiment thereof reference is had to theaccompanying drawings, in which like reference characters designate thesame parts in the several views, and in Which- Figure 1 is a plan view,the bur being indicated at the moment it is about to begin its cuttingoperation, the bur moving toward the right in such operation as depictedin the present illustration.

Fig. 2 is a vertical longitudinal section on the line 2-2 of Fig. 1.

eating the lever bar in retracted position;

and

Fig. 9 is a fragmentary side elevation indicating the manner of securingthe hand wheel sleeve to the shifting block stand as will be seen fromthe line 99 on Fig. 1.

While this specification is intended to be complete as'to the noveldetails of construction distinguishing it from the subject matter of theearlier patent, no attempt will be made herein to elaborate on thegeneral objects or purpose of this type of machine since such featureswere fully set forth previously.

10 indicates a main stationary base having at one end a girth 11 towhich, is fixed a stationary piston rod 12 hearing at its oppositeend' apiston 13. The cylinder 14 is reciprocated over the piston toward theright by power fluid admitted between the piston and the end cap 15, andtoward the left by power fluid admitted subsequently between the pistonand the end 16 of the cylinder. The upper portion of the carriage towhich the cylinder is connected may be termed a cover at 17 and this asindicated in Fig. 7 is provided with longitudinal inlet and waste ports18 and 19 respectively from each of which leads a branch port 18' or 19'to and from the valve mechanism of the cross feed motor. The ports 18and 19 communicate with a valve chamber 20 suitably bored out and fittedwith a liner 21 consisting of a short vertical cylinder within which vthe cross feed motor, being controlled by- .other.

is journaled a valve 22 controlling the power fluid for the maincarriage. Said liner is bored radially with a plurality of holesopposite each of the inlet and waste ports, the capacity of each groupof ports formed through the liner opposite each main port being equal toat least that of the main port.

Among the objects of the cylindrical liner are: First, the provision ofa structure adapting the use of a high quality of metal at moderate costwhich will resist corrosion and afford the best operating conditions;secondly, the relief from obligation of the builder of the machine toaccurately turn the chamber in which the liner is fitted, and thirdlythe formation of the small holes provides for the use of a softerquality of packing 23 which will glide freely over the holes than couldbe used in this type of valve if a large hole were formed in directcommunication with the valve.

lVith the valve adjusted as shown in Fig. 7 pressure fluid admittedthrough the port 18 and by-pass 24: through the valve' will pass thencethrough a longitudinal port 25 to the space between the piston and thecap 15 for the purpose of driving the carriage toward the right asviewed in Figs. 2 and 7. At the same time the same pressure fluid willpass through the auxiliary port 18 to the valve 26, (see Figs. 3 and Itwill thus be seen that the power fluid from the same source isapplicable directly to each of the valves 22 and 26, but said valves maybe actuated independently of each lVhen the power fluid is admittedthrough the valve as shown in Fig. 7 from the inlet 18 the waste fromthe left side of the piston 18 will pass out through the port 27.passageway 28 in the valve, and thence. out through the waste port 19.

The character of the valve 26 in most respects is similar to that of thevalve 22 especially with respect to the liner 29 in which the valve isfitted for oscillation. The valve as shown in Fig. 5 is set to releasethe bur 30 for withdrawal fromthe stone 31. Consequently at this timethe passage of the power fluid from the port 18 will be through theby-pass 32 through the valve, and thence through the port 33 to the rearof the piston 34 mounted in the cross feed motor cylinder 35. Duringthis release of the bur the waste water from the front side or left ofthe piston as shown in Fig. 3 will be discharged through the port 36 andby-pass 37 through the valve to the waste port 19.

Referring now more particularly to the valve construct-ion fixed to theupper end of the valve spindle is a pinion 38 with which mesh the teethof an internal rack 39 carried by a plate -10 journaled for oscillationaround a stud 11 fixed to a plate 42 and carried by the upper surface ofthe carriage and through which the valve stem is journaled. The rack 39is concentric with the stud 41 and is adapted to oscillate through asmall angle and limited by lugs l3 adapted to strike in alternationagainst a fixed stop 44. A slight angular rotation of the plate aroundits pivot acting upon the small pinion 38 will be sufiicient togive thevalve a quarter rotation for the purpose of reversing the direction ofmovement of the carriage first to make the cutting strokeand then makethe return idle stroke of the cutting bur. The upper portion of theplate 40 consists of a barrel 45 having a horizontal bore in which isslidably fitted a plunger 46 having on its inner end a head 47 and onits outer end a handle 18. The intermediate portion of the plunger isprovided with a radial pin '49 operating normally in an are shaped slot50 adjacent to one end of the barrel. Said slot terminates in ahorizontal slot 50' leading out from the outer end of the barrel or acollar 51 constituting the end of the barrel so as to bring the plungerinto the position shown in Fig.

8 with the pin 49 on the outside of the barrel. At this time the head 47is housed within a pocket 52 at the inner end of the barrel and in idleposition, at which time the operator w1ll manipulate-the handle 48 forrotation of the valve independent of any automatic mechanism associatedtherewith for normal operation. The pin 49, however, when in the areshaped slot 50 will hold the plunger extended as in Fig. 1 for automaticactuation.

The means for controlling the position and action of the bur 30 towardand from the stone 31 includes the cross feed motor. the piston andvalve. all of which havealready been referred to. Said motor includes aslide 53.n1ovable'in guideways 5-1 transverse to the direction ofmovement of the main carriage 17. The bur is journaled in a fork havinga shank 55 clamped adjustably in the slide. 56 constitutes an upstandingyoke at the front end of the slide in which the upper end of the pistonrod 57 is fixed rigidly. Consequently when the piston 34 is forcedforward or toward the stone the slide and parts carried thereby will becorrespondinglyactuated.

Oneof the most important features of novelty distinguishing thisinvention from the previous one lies in the means for actuating thevalve 22 through the plunger 46 as the result of the forward andrearward reciprocation, of the motor slide 53. the valve being actuatedthrough its full stroke of 90 degrees at the end of each re ciprocationof the slide and irrespective of the length of the stroke of the slide,at the same time the member actuated by the slide for oscillating thevalve mechanism operates only a short distance. This mechanism comprisesa box 58 slidable in dovetailed guideways 59 (see Fig. 2) between theslide 53 and the main valve and parallel to the slide, one side of thebox being open at 60 and into which the end of the yoke 56 projects.(See Fig. 6). This projecting end of the yoke is provided with a.threaded hole 61 through which the threaded portion of a feed screw 62extends. The feed screw has at one end a head 63 which is adapted toimpinge against the adjacent end of the box 58 when the slide 53 ismaking its forward stroke toward the stone whereby the box will becarried in the same direction for turning. the main valve -2'2- in aclockwise direction or to the position of Figs. 1 and 6. 64 indicates anextension of the box in which is journaled a sleeve 65 to which the handwheel 66 is connected for rotation of the sleeve, the interior ofwhichis polygonal for cooperation with a similarly formed shank portion 67 ofthe screw. (See Fig. 9). The sleeve 65 is held from endwise movementwith respect to the extension 64 by means of a clip 68 embracing acollar 69 formed on the sleeve. (See Fig. 9). Except for the slightreciprocation of the feed box 58 which in practice approximates aboutthree quarters of an inch, there is no reciprocation of the handle andhence it is very easy for the operator to have complete control of theadjustment of the screw at all times and with perfect safety. Thereciprocation of the feed box toward the stone is positively limited bymeans of a screw 70 locked in a lug 71 integral with the feed box, orits extension 64:, said screw being adapted to impinge directly againstthe main carriage. This stop mechanism acts in conjunction with thestops 43 and 44. The motor piston 34. under the force of the motivefluid carries the slide 53 and the bur toward the stone and thevariation or adj ustment of the length of such stroke or movement of theslide and bur is determined delicately by the rotation of the screw 62in the yoke 56 whereby the space between the head 63 and the adjacentend of the box 58 I is varied. More definitely at the end of each strokeof the bur across the stone the operator will give the hand wheel avsliding turn so as to withdraw the head 63 slightly from the end of thebox, or with a left turn as shown in Fig. 6. Consequently on the nextforward stroke of the bur toward the stone the slide will move a littlefarther before the screw will act to shift the box and cause thereversal of direction of the main motor. When the cross feed motor isgiven its upward stroke thelyoke 56 as it nears the end of its strokewill strike against the opposite end of the box and so cause the mainvalve to be reversed again. The connection between the plunger head *7and the box depends upon a. clip 72 adjustably fixed upon the uppersurface of the box as shown in Fig. 1. and which has fairly closecontact with said head when the head is in operating position orextended around the pocket 52.

The stem of the valve 26 is fixed to a pinion 73 meshing with aninternal rack 7% carried b a plate 75 and pivoted on a stud 76. ee Fig.3). These parts are similar in construction and action to thecorresponding parts of the main valve already described. A handcontrolled plunger 77 has at one end a head 78 and at the other end ahandle 7 9, the control and manipulation of this plunger being similarto that of the plunger 46. The head 78 in normal automatic operation isadapted to impinge against a stop device 79 at either end of the base 10just as the main carriage is approaching the limit of such stroke and byactuating said head relatively to cause a slight rotation of the plate75 the valve 26 will be turned through 90 degrees to cause the reversalof the piston 34. As in the previous patentwhen the main carriagereaches the end of one reciprocation the cross feed motor will carry thebur into engagement with the stone and by the time the bur reaches thestone the valve will have been shifted to cause the motive fluid toactuate the main carriage parallel to the stone, the rotation of whichstone will cause the rotation'of the bur and the dressing of the surfaceof the stone. VV-hen the cutting stroke of the bur across the faceof'the stone is completed the stop 79 at the point to be struck by thehead 78 of the cross motor valve structure causes the shifting again ofthe valve 26 to cause the power fluid to withdraw the bur from the faceof the stone as shown in dotted lines in Fig. 1. During this movement ofthe cross feed motor the main carriage will have continued in its samedirection until limited by the striking of the hub 16 of the cylinderend 16- against. the piston 13. Immediately thereafter, however, theoutward movement of the cross feed motor and bur from the stone willeffect the reversal of the main carriage valve to .the position shown indotted lines in Fig. 1 so that the motive fluid will return the carriageand bur idly toward the left. The plunger head 78 at this time will bein its forward position and when it strikes the lug 79 atthe oppositeend will cause the reversal of the valve '26 and the forward movement ofthe slide and bur into cutting position again. The movement of thecarriage toward the position in full lines in Fig. l is positivelylimited by contact of the adjustable screw 80 impinging against theouter end of the piston rod 12 or piston fixed-thereto. (See Fig. 2)

The base 10 upon which are fitted and supported all of the mechanismabove described is adapted to be adjusted around the axis of the pistonrod 12 as shown in Fig. 3 by virtue of bolt and slot connections 81 withthe main support and thereby the angle of incidence between the bur,fork and the stone may be varied, an item of importance in manyinstances.

In the practice of this invention it frequently happens that the shim,chip or the like of wood or other material will be caught between thebur and the stone when power is applied to the bur tending to hold itagainst the stone. This circumstance is apt to prove disastrous unlessthe pressure fluid can be relieved promptly as by means of asafety'valve 82 of any suitable nature shown herein as applied to theouter end 83 of the cylinder 35. This valve per 86 may be of anysuitable construction, but is adjusted to act at a sufiiciently higherpressure than the normal pressure of the fluid so as not to interferewith the normal operation of the machine. In this connection it is to beobserved that for the best operation of the bur the power fluid actingto hold it in contact with the stone should be substantially constant inforce. In order, therefore, to maintain this force constant or at amaximum I provide some suitably arranged check valve 8% between theinlet port 18' and the valve 26. This valve Si is acted upon by a spring85 tending to close the valve in a reverse direction to the direction ofthe power fluid. Under normal conditions the power fluid is maintainedat a substantially uniform pressure throughout both motors, the valve 84being held open against the force of the spring 85. If, however, thecutting operation is in progress and with full pressure in the crossfeed motor cylinder and the pressure at the source of the motive fluidshall drop without the valve 84 the pressure in the bur actuating motorwould likewise drop and cause an uneven action of the bur on the stone,but with the valve as shown the instant pressure back of the cross feedmotor drops the valve 8-;t immediately closes and thereby the fullpressure is sustained in the cylinder 35. This machine is adapted foreither right or left cuts with corresponding readjustment of thecontrolling devices. Consequently the casing of the valve 26 is providedwith a plug 86 adapting the rotation of the check valve to the otherside.

I claim:

1. In a machine of the class set forth, the combination of a machine, afluid pressure motor to reciprocate the carriage, a cutting tool, across feed motor including a slide to carry the tool in directionstransverse to the movement of the carriage, independent valve means forsaid motors, and means to convey power fluid toward and from both valvemeans through the body of said main carriage. I

2. In a machine of the class set forth, the combination of a tool, fluidpressure means to actuate the tool in one direction, a main support forthe tool and its actuating means, a fluid pressure motor to actuate saidmain support in a different direction from that of the tool, a source ofpressure fluid common to both motors whereby both motors may be actuatedat the same time, and automatic means to maintain a substantiallyuniform pressure in one of the motors if the pressure acting on theother motor should drop.

3. In a machine of the character set forth, the combination of a cuttingtool, a reciprocating fluid motor to actuate the tool in certaindirections, a main carriage supporting the tool and its motor, a secondmotor toactuate the carriage in different directions from the directionof movement of the tool, a source of power fluid leading through themain carriage to both motors, and automatic means serving to maintain asubstantially uniform pressure in the tool motor even though thepressure through the main carriage motor may fluctuate.

4. In a grinder stone dresser, the combination with a cutting tool,automatic means to actuate the tool toward and from the face of thestone, other means to carry the tool in directions at right angles tothe aforesaid movement, and movable valve means to control the action ofthe last mentioned means, of means operated from the first mentionedtool moving means to shift the valve means and including a box movableparallel to the movement of the tool but to a less distance, and amember carried by the box having constant engagement with a member projectin from the valve.

5. n a machine of the class set forth, the combination of a carriage, amotor to reciprocate the carriage, a cross feed motor supported upon thecarriage, a tool slide reciprocated by the latter motor at right anglesto the direction of movement of the carriage, a box mounted forreciprocations parallel to the slide but to a less distance, a valve tocontrol the first mentioned motor, said valve including a plunger, meansto. cause the movement of the box from the slide as the slide reachesthe end of its reciprocation, and a plunger having a projecting end anda member serving .to make constant connection between said plunger endand the box.

6. In valve actuating means for grinder stone dressers, the combinationwith a rotary valve, a plate pivoted on an axis parallel to the axis ofthe valve, said plate having an internal gear rack, a pinion fixed tothe valve stem and meshing with said rack, and

a member carried by the plate transverse to its pivot and having a shortarm projecting beyond the pivot from the rack, of a slidable plate, anda member fitted in said barrel bore with one end projecting beyond theaxis of the plate remote from the valve connections, of, a slidingmember and a clip carried by said sliding member having close engagementwith the projecting end of the iember carried by the barrel whereby ashort movement of the sliding member will cause a considerable movementrelatively of the valve.

8. In a valve actuating means for grinder stone dressers, thecombination with an oscillating valve plunger, of a box, means to"support the box for reciprocations transverse to the axis of the valve,permanent operative connections between the box and said plunger, apower operated device movable parallel to the box, lost motionconnections between the power device and the box providing for greatermovement of the power member than for the box, and means to cause thelimit of extent of movement'of the box.

9. In a grinder stone dresser, the combination of a tool carriercomprising a slide, means to operate the slide, a slidable box parallelto the slide, said box having an open side and the slide havinga'projection extending into said open side of the box, a,

feed screw threaded in said projection and adapted to impinge against aportion of the box as the slide approaches the end of its reciprocation,a power controlling valve, and connections between the box and the valveto cause the quick movement of the valve as a result of a short strokeof the box, substantially as set forth.

.10. In controlling means for a grinder stone dresser, the combinationof a tool carrier including a slide movable toward and from the stone, abox arranged to reciprocate parallel to the slide but to a shorterdistance, said box having an opening atone side of the slide having aprojection extending through the opening into the box, an adjustablefeed screw threaded in said extension and adapted when the slideapproaches the end of one reciprocation to strike against a portion ofthe box to move the box, a slide extension being adapted to strikeagainst a portion of the box when the slide approaches the end ofanother reciprocation, a power controlling valve, and connectionsbetween the box and the valve serving to cause a relatively largemovement of the valve from a small movement of the box in eitherdirection;

11. A valve mechanism for grinder stone dressers, the combination with avalve, a plateeadjacent to the valve, said valve and plate being mountedfor relatively great reciprocation in a direction at an angle to thedirection of movement of the plate, said plunger having means for handmanipulation thereof independent of the automatic means.

FRED E. RILEY.

and small movements respectively, the

